Abstract: The Project Management Institute states (2008, p419) that communication is the most important competency skill that a project manager may possess. With very large projects, or programs, the stakes are very high and consequently communication, as a significant factor in the success or failure of its outcome, cannot be overemphasized. This paper will show several examples where inadequate communication led to the failure of very large and highly visible programs, including the Challenger Space Shuttle program in 1986, the Columbia Space Shuttle program in 2003, and the Deepwater Horizon explosion in 2010. In large programs such as these, the ability to communicate the correct information to the correct party at the correct time is hampered by its size, with sometimes up to thousands of team members and geographical as well as hierarchical distance as when multiple companies are brought together to achieve a common objective. This paper will analyze the root cause behind the communication failures and will suggest techniques that can be used to avoid or mitigate such failures. What may have worked at the project level will need to be altered to accommodate program management since the complexities at the program level are many factors greater.